nltk.tokenize.sexpr_tokenize

nltk.tokenize.sexpr_tokenize(text)

Return a list of s-expressions extracted from text. For example:

>>> SExprTokenizer().tokenize('(a b (c d)) e f (g)')
['(a b (c d))', 'e', 'f', '(g)']

All parentheses are assumed to mark s-expressions. (No special processing is done to exclude parentheses that occur inside strings, or following backslash characters.)

If the given expression contains non-matching parentheses, then the behavior of the tokenizer depends on the strict parameter to the constructor. If strict is True, then raise a ValueError. If strict is False, then any unmatched close parentheses will be listed as their own s-expression; and the last partial s-expression with unmatched open parentheses will be listed as its own s-expression:

>>> SExprTokenizer(strict=False).tokenize('c) d) e (f (g')
['c', ')', 'd', ')', 'e', '(f (g']

Parameters

text (str or iter(str)) – the string to be tokenized

Return type

iter(str)